#include <iostream>
#include <queue>
#include <algorithm>
#include <cmath>
#define ll long long

using namespace std;

vector <ll> x,mag;

void magassag(ll csp, ll n)
{
	if (csp >= n)
	{
		mag[csp] = x[csp];
		return;
	}
	magassag(csp * 2, n);
	magassag(csp * 2 + 1, n);
	mag[csp] = max(mag[csp * 2], mag[csp * 2 + 1])+x[csp];
}

ll j;

int main()
{
	ll n, k;
	cin >> n >> k;
	ll csp = pow(2, n)-1;
	x.assign(csp + 1, 1);
	mag.resize(csp + 1);
	x[1] = 0;
	for (ll i = 1; i <= k; ++i)
	{
		ll a;
		cin >> j >> a;
		x[j] = a;
		magassag(1, pow(2, n-1));
		cout << mag[1]<<"\n";
	}

	return 0;
}
/*3
0 2 1 1 10 3 4*/